A new study published in the journal of Applied and Environmental microbiology has determined that the optimal health benefit associated with probiotics is tied to the food, beverage, or other material carrying the probiotics. Dairy products are the most popular method for delivering probiotic strains, but no specific study has investigated which methods provides the most optimal benefit.

The scientists used a mouse model of colitis or inflammation to investigate the impact of lactobacillus casei BL23. Mice the received the probiotic in milk had reduced symptoms compared to mice that were fed the probiotic without milk or received the probiotic in a nonfood supplement.

“Our findings indicate that the manner in which a probiotic is delivered–whether in food or supplement form–could influence how effective that probiotic is in delivering the desired health benefits,” said corresponding author Maria Marco, PhD, an associate professor in the Department of Food Science and Technology, at the University of California at Davis.

“Strains of L. casei are commonly added to dairy products as probiotics and, while strain BL23 is not commercially available, it is genetically similar to commercial strains and has also been studied for its capacity to prevent or reduce intestinal inflammation,” she added.

“The question of whether it makes any difference to consume probiotics in dairy products rather than other foods or nutritional supplements has not been systematically or mechanistically investigated in clinical or preclinical studies”. “Because we know that bacteria can adapt to their surroundings, we thought the conditions that probiotics are exposed to prior to ingestion might influence their capacity to maintain or improve human health.”